Abstract

As a result of the coupling between the spin of the earth and the spin angular momentum of the electron and proton, terrestrial atomic hydrogen should exhibit a nonforbidden circular birefringence and consequent optical rotary power for microwave radiation near the 1S_1/2(f= 1) - S_1/2(f = 0) hyperfine splitting frequency of 1420 MHz. Rotation of the earth splits the degenerate 1S(f= 1) magnetic substates, thereby giving rise, through a magnetic dipole interaction with circularly polarized microwaves, to chirally asymmetric magnetic permeabilities. The predicted circular birefringence can be some 10 orders of magnitude larger than that previously attributable to chirally asymmetric electric permittivities deriving from virtual electric dipole transitions between electronic manifolds induced by incident radiation falling in the visible and UV portions of the spectrum.¹

© 1991 Optical Society of America